Radio antenna question

I just replaced the fixed mast radio antenna on my 71. I noticed 2 differences. 1-it's a little shorter. 2-the ball at the top is smaller then the original. The new one is nicer looking, but not as much of a difference as I thought it would be. My questions are....are the original ones hard to find? Do they make a "correct" repo? Should I put the original back on, or keep it in a safe place for later down the road? Thanks to all who help.

Is complete originality that important to you? I would be more concerned about the antenna's performance and reception.

I don't know if there are any "true" reproductions on the market. GM may have had several vendors making them originally under the GM name and part number and there could well have been dimensional variations, so who could say what is truly authentic unless it came out of a GM parts box.